Bidding is now open for construction of an Eastsound wetland that will detain and treat road runoff and stormwater.

The first stage began last September, when public works laid pipes to handle water flow. Bids will be awarded July 11 and construction will start in September for the final phase of building the wetland.

“Fingers crossed, we’ll get done before the rains start in November,” said project manager Shannon Wilbur during an open house on June 16.

The constructed wetland will be installed on the Mount property, which the county has owned since 1994. It will be located behind the band shell in the Village Green and is intended to treat road runoff/stormwater prior to discharge into Fishing Bay. Although a design was drawn up in 2006, some modifications have been made due to regulatory changes and input from the community aesthetic design review committee at a series of meetings this winter. An EPA grant is funding the project.

Plans for the .9-acre wetland include the following.

• Construct a sedimentation basin and constructed wetland with 1.13 acre-feet (370,000 gallons) of treatment volume, utilizing the existing small wetland on the site, which will be protected during construction by a fence. The sedimentation basin will slow the flow of stormwater, thus allowing pollutants and particles to settle out. As the stormwater flows through the wetland, it will be further treated by plants specifically chosen for their ability remove pollutants and by infiltration through the soil. Ultimately, the treated stormwater will be discharged to an existing piping system and into the bay. Monitoring will be conducted on the inflow and outflow to document the treatment efficiency.

• Construct piping to convey future stormwater flows from the A Street and Fern Street/North Beach stormwater systems. This will be done during phase 3, which is intended to be designed in the fall and constructed next year. Additionally, construct outlet piping from the constructed wetland to tie into the Phase I stormwater system installed in 2010.

• Construct a trail around the perimeter of the site to tie into the Village Green and add interpretation signs designed locally.

We are saving a group of eight conifers and the remaining plants and trees are coming down,” Wilbur said. “Some of trees’ roots are being used for ‘log root wads,’ which helps the water flow meander through. They will be placed in strategic locations.”

Once the wetland is constructed, cobbles, top soil and nearly 400 trees and shrubs and 5500 bulbs/bare root plants, as well as nearly 2000 square yards of wetland seeding with sedges and rushes, will be planted in and around the wetland both for aesthetic and functional reasons.

Eastsound resident Sadie Bailey, who has been in opposition of a wetland design approach that removes so many trees, was in attendance at the open house. She thanked public works for holding the event and encouraged the county to offer more information to the community before construction begins.

“Anyone with questions or concerns should contact me at 376-3796 so we can get those questions addressed at the next workshop,” Bailey told the Sounder. “The reason I am encouraging open houses is that we all had three days notice of this most recent event because the final plans weren’t out in time. The public needs to have proper notification.”

To submit feedback to the county on this project, contact Wilbur at 370-0522 or shannonw@sjcpublicworks.org.